This invention relates to parenteral administrations systems and fluid regulating devices, and most particularly, to an improved fluid regulating device for use in a parenteral administration system.
Parentral administration systems are utilized to transfer intravenous solutions to medical patients. Such systems typically include a fluid supply container, a parentral needle and tubing interconnecting the fluid supply container with the needle. Transfer of the solution is achieved through gravity by suspension of the container above the patient.
A significant problem in the utilization of parentral administration systems is the regulation of the flow of solution to the patient. This problem has along been known, and has resulted in a variety of fluid regulating devices. As an example, roller clamps have been attached to variably compress the tubing and thereby provide a variable rate of flow. Generally, these devices all control fluid flow in the manner of roller clamps, i.e., by pinching force on the tubing. While a few of these devices have proved highly useful, most are cumbersome, inaccurate, incapable of rapid variation or hazardous. No one device fully satisfies long-felt needs for such devices.
A principal reason for the inadequacies of these devices is that the pinching of typical tubing results in deformation without reduction of the cross-sectional area of the internal passageway, until the tubing is almost totally collapsed. As a result, fluid flow varies from substantially full flow to zero flow over a minute range of deformation near total tubing collapse. Truly accurate control of deformation in this range is extremely difficult. Another reason for the inadequacies of prior art devices is that typical tubing is not satisfactorily resilient when pinched. As a result, accurate variation of fluid flow through the tubing from a pre-selected flow to a desired flow is also difficult, if not impossible.